'use strict';
var Cesium = require('cesium');

var defaultValue = Cesium.defaultValue;

module.exports = addToArray;

/**
 * Adds an element to an array and returns the element's index.
 *
 * @param {Array} array The array to add to.
 * @param {Object} element The element to add.
 * @param {Boolean} [checkDuplicates=false] When <code>true</code>, if a duplicate element is found its index is returned and <code>element</code> is not added to the array.
 *
 * @private
 */
function addToArray(array, element, checkDuplicates) {
    checkDuplicates = defaultValue(checkDuplicates, false);
    if (checkDuplicates) {
        var index = array.indexOf(element);
        if (index > -1) {
            return index;
        }
    }

    array.push(element);
    return array.length - 1;
}
